Winds travelling at more than 100km/h tore through the city overnight, ripping the roof off a granny flat in Doubleview, collapsing a ceiling in Joondalup and blowing in the windows of a house in City Beach.

More than 17,000 are believed to be without power because of the storm, mostly in the Perth hills.

State and Emergency Services (SES) have recorded 70 calls for help since 7am, with a total of 125 incidents logged since 6pm last night and 240 properties impacted.

Damage has been reported in coastal suburbs from Two Rocks to Rockingham and all SES units in the metropolitan area have been activated with volunteers in Northam called in for backup.

A series of cold fronts have been lashing the city since Friday, with Rottnest, Ocean Reef, Mandurah and Bickley some of the worst hit areas.

Ocean Reef recorded a wind gust of 107km/h and gusts of 115km/h were recorded at Rottnest, where ferry services have been cancelled.

The ports of Fremantle and Kwinana ports have suspended operations until midday.

Across the state, Cape Naturalist and Cape Leeuwin recorded wind gusts of up to 109km/h. There have been reports of fallen trees and minor damage to homes in Bunbury, Busselton and Capel.

The WA Bureau of Meteorology says it is the wettest day of the year.

Flights from Perth’s international terminal are running half an hour behind schedule, and Main Roads are urging motorists to slow down and take care in the inclement weather.

Near the city, waves from the Swan River were lapping around peak hour traffic on the Kwinana Freeway this morning, while Riverside Drive and parts of Beaufort St have isolated flooding.

Traffic lights are out on the intersection of Great Eastern Highway and Stoneville Rd in Mundaring and at the junction of Kalamunda Rd and Gooseberry Hill Rd.

WA Bureau of Meteorology climate information officer John Relf says 23.2mm of rain has fallen overnight taking Perth much closer to the 177mm average with 147.8mm of rain recorded this month.

“We have exceeded last year’s June rainfall of 142mm,” he said.

Heavy rain has been reported from Collie to Walpole.

WA Water Corporation spokeswoman Clare Lugar says dams should have now started benefiting from the all rainfall.

“Up until Friday the streams hadn’t started to flow,” Ms Lugar said. “But we are expecting it to have begun flowing over the weekend.”

The wild weather is expected to ease up later tonight with fine weather forecast by Thursday.